Small Acute Benefits of 4 Weeks Processing Speed Training Games on Processing Speed and Inhibition Performance and Depressive Mood in the Healthy Elderly People: Evidence from a Randomized Control Trial

Abstract

Background: Processing speed training using a 1-year intervention period improves cognitive functions and emotional states of elderly people. Nevertheless, it remains unclear whether short-term processing speed training such as 4 weeks can benefit elderly people. This study was designed to investigate effects of 4 weeks of processing speed training on cognitive functions and emotional states of elderly people. Methods: We used a single-blinded randomized control trial (RCT). Seventy-two older adults were assigned randomly to two groups: a processing speed training game (PSTG) group and knowledge quiz training game (KQTG) group, an active control group. In PSTG, participants were asked to play PSTG (12 processing speed games) for 15 min, during five sessions per week, for 4 weeks. In the KQTG group, participants were asked to play KQTG (four knowledge quizzes) for 15 min, during five sessions per week, for 4 weeks. We measured several cognitive functions and emotional states before and after the 4 week intervention period. Results: Our results revealed that PSTG improved performances in processing speed and inhibition compared to KQTG, but did not improve performance in reasoning, shifting, short term/working memory, and episodic memory. Moreover, PSTG reduced the depressive mood score as measured by the Profile of Mood State compared to KQTG during the 4 week intervention period, but did not change other emotional measures. Discussion: This RCT first provided scientific evidence related to small acute benefits of 4 week PSTG on processing speed, inhibition, and depressive mood in healthy elderly people. We discuss possible mechanisms for improvements in processing speed and inhibition and reduction of the depressive mood. Trial registration: This trial was registered in The University Hospital Medical Information Network Clinical Trials Registry (UMIN000022250).

Keywords: cognitive training; depression; inhibition; processing speed training; video game.

FIGURE 1

Consolidated standards of reporting trial (CONSORT) diagram.

FIGURE 2

A processing speed training game and knowledge quiz training games. For connection numbers (A), participants connect numbers in number order. In the case of (A), participants are asked to draw the lines from a smaller number to a big number as quick as possible (1→2→3→4→5). For translating figures to numbers (B), participants select numbers related to target figures. The rule is presented at the top left corner of the screen. The numeric keypad (response pad) is present at right side of the screen. In the case of (B), circle correspond to 1, triangle correspond to 2, and star correspond to 3. The rule is changed every game. The target figure is presented around the center of the screen. In the case, participants are asked to touch the specific number (3) related to the target figure (triangle) as quick as possible. For calculation with whack-a-mole (C), participants conduct simple calculations with tapping targets. The numeric keypad (response pad) is present at right side of the screen. In the case of (C), the tapping target is a mole. A numerical expression is presented around the center of the screen (e.g., 1 + 9). The tapping target is moving until participant tap the target and the number of the tapping target increase during the game. In the case, participants are asked to response the answer of the numerical expression (10) and to tap the target as quick as possible. For the meaning of words (D), participants answer a pronunciation of Kanji. A quiz is presented at the top of the screen. In the case of (D), the target Kanji (: squilla) is presented. The five pronunciations are presented. In the case, the first pronunciation is dojyou (: loach), the second pronunciation is saba (: mackerel), the third pronunciation is kaba (: hippopotamus), the fourth pronunciation is iwana (: char), the fifth pronunciation is syako (: squilla). Participants are asked to select the corrected pronunciation of the target Kanji (in this case, the corrected answer is the fifth pronunciation: syako).